The purpose of this research is to gain knowledge and develop techniques that will aid in determining the amounts of dietary and other substances required for optimum health in humans; aid in the early diagnosis of illness in humans; and aid in fundamental research on the molecular biology of human illnesses. We are especially interested in single procedures that have a broad applicability to many different states of health and illness and that measure a large number of characteristics in human body fluids so as to take biochemical individuality into account. We have developed experimental techniques based on profile measurement and pattern recognition of urinary chromatograms, and we have initiated investigations into the possibility that direct introduction of urine samples into mass spectrometers may be superior to chromatography for this purpose. In this proposal we request funds for development of a new kind of field ionization mass spectrometer, for continued support of our mass spectrometry identification work, and for experiments to test the applicability of mass spectrometers for the purposes of producing faster, better, and cheaper methods of diagnosis and of following the course of disease and the effectiveness of prophylactic and therapeutic measures.